Shift ciphers are the most basic form of encryption that can be used, the only problem is that they are not very secure ciphers. The only time a turn code can be safe, it is also perfectly safe. This “perfect security” only occurs when a rolling code is used on a single letter of plaintext and no more. When considering practicality, this is not an efficient use of message encryption. It is simply not practical to send a single encrypted letter. To understand the insecure encryption of a turn cipher, you must first understand how a turn cipher encrypts a message. The way a turn cipher works is that a letter in the plaintext is replaced by another letter in the alphabet. When using the standard English alphabet you will have twenty-six different letters with which you can encrypt the plaintext, for example, the plaintext letter "e" could be encrypted into the ciphertext letter "m", which means that the letters would be shifted by eight. The “key” to your ciphertext is now eight, because it takes eight letters from “e” to get to the letter “m”. With this information, you can see why a simple scroll code could be easily deciphered using just a couple of letters. For example, let's say someone is trying to decrypt a stolen piece of ciphertext, the only way this person will be able to decrypt this piece of text is if they know the way it is encrypted and the key. The important thing to remember is that the thief may know how it is encrypted but, unless he knows the key, he will not be able to decrypt the text. The key is the most important part in any ciphertext and should be known only to the sender and recipient of the ciphertext. Therein lies the problem with scrolling code. Discovering the key would be a thief's main goal, because without it it is not possible to read the ciphertext. Once they figure out what the key is, the journey to deciphering the message and reading the plaintext is short. If the ciphertext is longer than one letter, the key will be able to decrypt each individual letter back to the original plaintext, thus decrypting the entire message. For example, if the plaintext was the word please and was encrypted using a rolling cipher with a key of eight, the ciphertext would be xtmiam.